A119832 Bi-diagonal inverse of (3n)!/(3k)!.
1, -6, 1, 0, -120, 1, 0, 0, -504, 1, 0, 0, 0, -1320, 1, 0, 0, 0, 0, -2730, 1, 0, 0, 0, 0, 0, -4896, 1, 0, 0, 0, 0, 0, 0, -7980, 1, 0, 0, 0, 0, 0, 0, 0, -12144, 1, 0, 0, 0, 0, 0, 0, 0, 0, -17550, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -24360, 1
Offset: 0
Examples
Triangle begins 1, -6, 1, 0, -120, 1, 0, 0, -504, 1, 0, 0, 0, -1320, 1, 0, 0, 0, 0, -2730, 1, 0, 0, 0, 0, 0, -4896, 1, 0, 0, 0, 0, 0, 0, -7980, 1, 0, 0, 0, 0, 0, 0, 0, -12144, 1, 0, 0, 0, 0, 0, 0, 0, 0, -17550, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -24360, 1
Formula
Column k has g.f. x^k(1-b(k+1)x) where b(n)=3n(3n-2)(3n-1)=A054776(n).
Comments